1. Field of the Invention
The present invention relates generally to a discharge auger system for a bulk material storage receptical for fertilizers and the like. More particularly, the present invention relates to an auger system for a trailer wherein the auger folds between a stowed position and a discharge position for dispensing of stored material. Known related prior art may be found in U.S. Class 414, subclass 523, among others.
2. Description of Prior Art
It is known to provide bulk material tenders with pivoting unloading tubes or auger delivery sections that move between a transport or stowed position and a delivery or discharge position. During transport, a portion of the auger is generally positioned alongside the tender while that portion pivots to a position generally traverse to the tender for unloading the tender toward a side during material discharge. As will be appreciated by those skilled in the art, it is critical to efficiently and effectively position the discharge auger tubes for unloading, while providing suitable communication for the material between the tender and the discharge auger.
While the present invention may be utilized with fixed or permanent storage receptacles, it is particularly well suited for use with mobile bulk material tenders. Bulk material tenders of the type contemplated for use with the invention generally deliver large amounts of particulate material, usually in the range of 10 to 40 tons in a single load. This material is typically discharged by the auger system at rates approaching 4,000 lbs/min. Even though large loads are the norm, the auger system usually unloads the tender in a matter of minutes. As may be easily imagined, the time required for the operator to properly position the auger system generally equals or exceeds the time required for discharging the tender load.
The known prior art have utilized articulated auger tubes and discharge auger tubes having multiple sections which are disassembled for stowing and must be reassembled for discharge. These dissassembling augers are time consuming and labor intensive, especially given the time requirements for unloading the tender by the auger system. Other types of prior art devices provide auger systems that are otherwise unduly complex, many having multiple sections that pivot or otherwise move in multiple axes. These complicated auger systems do not normally improve the overall quality of the material delivery but rather add to the costs for such delivery.
Several examples of overly complex devices are shown in the prior art, including U.S. Pat. Nos. 2,877,914, 3,326,397, 4,613,275, all of which are of general relevance. Another complex, though intersting, device is shown in U.S. Pat. Nos. 3,642,155 and 3,770,101, both to Carlson. The Carlson device appears to comprise an articulated unloading boom hinged to one end of a transport body for movement between a travel position and an unloading position. In the travel position, the boom is unfolded against one side of the body while the hinged boom sections are aligned in the unloading position. The boom comprises an upper section and a lower section pivotally joined by a hinge. A hydraulic actuator rotates the upper section between its travel position and its aligned unloading position relative to the lower section.
Another interesting device is shown in U.S. Pat. No. 4,093,087 to DeCoene shows a system for moving an unloading auger tube having a main segment and an end segment between the transport position and a selected unloading position. The end segment is angled with respect to the main segement and it is pivotally mounted on a lower inclined portion of a side wall so as to extend away from the central, vertical fore aft plane of the vehicle. The auger segments are disposed predetermined angles to facilitate auger pivoting about a single axis located perpendicular to the inclined mounting surface of the side wall for movement between the stowed position and a discharge position.
Another overly complex device is shown U.S. Pat. No. 4,613,275 to Karlowski. The Karlowski patent shows an articulated support arrangement for attaching an auger system to a side wall of a truck. This arrangement permits the auger to move between a storage position against the side wall to an operating position parallel to the truck rear. The auger conveyor is supported by a swingable material conveyor support. The support includes a pivot arm moving arcuately about a hinge with a terminal clamp intermediately securing the arm to the auger conveyor. The clamp pivots about a second hinge and third hinge to enable the auger conveyor to pivot about multiple axes when moving between its storage and operating positions. Other patents showing complex devices of generally lesser relevance include U.S. Pat. Nos. 3,322,257 3,391,778, 3,638,816, 4,218,169, 4,419,037, 5,520,495 and 5,615,990.
While the above mentioned prior art devices are generally too complicated for efficient practical use, several simplistic devices are also known in the art. These devices typically require little time for conversion between the transport position and the delivery position.
For example, U.S. Pat. No. 4,742,938 to Niewold shows a positioned mechanism for an auger in which the auger is hydraulically swung between its transport and working positions. The auger tube is mounted at its lower end by a swivel to a wall of a hopper, permitting the auger tube to swing into place via a hydraulic cylinder.
Similarly, U.S. Pat. Nos. 4,427,105,5,108,249,5,538,388 and 5,655,872 all show devices that pivot between a transport and working position via a hydraulic cylinder and a terminally hinged auger tube. However, all of these devices pivot about a terminal hinge. In other words, the hinge is located at the end of the tube.
A very interesting device is shown in U.S. Pat. No. 5,468,113 to Davis. Davis shows an auger that pivots in multiple axes about an intermediary point proximate one end. Apparently, the auger moves between the transport and delivery positions by pivoting about a first pivotal mount that cooperates with a second pivotal mount. When in the delivery position, the auger maintains dust-free communication with the storage receptacle.
The known prior art fails to provide an efficient auger system for unloading bulk material tenders that overcome problems associated with efficient and practical conversion between the stowed and discharge positions while avoiding unnecessarily structurally instable pivotal couplings. Known multiple segmented or articulated pivoting auger systems are usually difficult and time consuming to convert between stowed and discharge positions. Further, known prior art devices with auger systems that pivot in multiple axes during conversion between stowed and discharge positions often require experienced operators to properly position the auger system. Prior art devices using couplings having terminal hinges or cylinders are inherently instable because the entire wieght of the auger is pivoted about a terminus. In particular, no known prior art device distributes the stresses generated during the conversion of the auger system between its stowed and discharge positions adequately.
Thus, a desirable improvement to the art would be an auger system for a tender that enabled an unskilled operator to quickly and efficiently convert the system between a stowed and a discharge position. A particularly desirable improvement would be an auger system that adequately distributed stresses generated during auger conversion.